By Louis Navellier for InvestorPlaceNEW YORK ( InvestorPlace) -- The best stocks for 2011 continue to be commodity stocks for many investors. Gold and silver prices have rolled back from highs at the end of 2010, but are still near record levels. Thanks to the prospect of commodity inflation due to a weak dollar and glimmers of an economic recovery, many experts are predicting gold prices to rally and silver to continue to set new highs in the months ahead. Along with these precious metals, some expect other materials like copper and steel to soar as well. It's shaping up to be a big year for metal and mining stocks -- if you believe the hype. However, not all miners are in the clear even if you believe in this commodity inflation prediction. The fact is that some poorly run metal and mining stocks have lackluster fundamentals and should be sold immediately. Here are six top miners that should be dropped from your stock portfolio. Posco Operating in Korea, Posco ( PKX) is an integrated steel producer. Over the past 12 months, PKX's stock performance has been anything but thrilling. Since last January, this stock is down 21%, compared to gains of 11% and 10% for the S&P 500 and Dow Jones Industrial Average, respectively. Another startling number is Posco's quarterly revenue growth which was down 15% year over year. Sell now. Related Article: When to Sell Stocks and Stocks to Sell Gerdau ( GGB) Gerdau ( GGB) produces long-rolled steel in Brazil, and operates separate steel mills in the same country. Over the past 52 weeks, this mining stock has posted a loss of 19%, compared with gains in the broader markets. Shareholders are also not thrilled by GGB's earnings. Experts are predicting earnings of just 18 cents a share this quarter, compared with EPS of 53 cents, which GGB posted this time last year. GGB may be one of the cheaper stocks on this list with a yearly range of $11.49 to $17.99, and should still be sold now before it loses any more value. Related Article: 5 Reasons Silver Glitters More Than Gold Aluminum Corp. of China Aluminum producer Aluminum Corp. of China ( ACH) also has operations in bauxite mining, alumina refining, primary aluminum smelting and aluminum fabrication. Since last January, this mining stock has dropped 29%. Shareholders must also not be pleased by the company's net profit margin of just 1% that was posted in its last income statement. The stock doesn't seem to be rebounding at all either, and is down 7% over the past three months.